Kansas City Chiefs quarterback Chase Daniel, left, and Jamaal Charles, right, chat with general manager John Dorsey following NFL football training camp Thursday morning Aug. 14, 2014, on the Missouri Western State University campus in St. Joseph. Mo. (AP Photo/St. Joseph News-Press, Todd Weddle)

KANSAS CITY, Mo. (AP) — Jamaal Charles made it through every hit from Derrick Johnson, every shot from Eric Berry and every tackle from the rest of the Chiefs’ defense during three weeks at Missouri Western.

It wasn’t until he was leaving their training camp home that he got hurt.

Charles was in the process of moving out of the dorms last Thursday, when the team was getting ready to shift the rest of camp to their own practice facility, when he came to a grassy slope. He wound up slipping just a bit and turned his foot just enough to set alarm bells ringing.

X-rays and MRI exams ensued, and Charles did not make the trip to Carolina for Sunday night’s preseason game against the Panthers. And while all the tests came back negative, coach Andy Reid said Monday that he’s unsure just how long the explosive running back will be out.

“He’s feeling better today. We’re optimistic about it,” Reid said. “Initially there was a little concern, but he had all stuff done to it and everything is clear.”

Reid did not say whether Charles will practice this week, or whether he’ll be available when the Chiefs host the Minnesota Vikings for their third preseason game Saturday night.

“I don’t know if there is any other guy in the league like him. You can’t replace him,” Chiefs quarterback Alex Smith said, “but that’s the NFL. It’s every team. If a guy goes down, the next guy has to step up and we got to go. We all have to take up the slack as a group.”

The health of Charles is hardly the only cause for concern in Kansas City these days.

The Chiefs’ offense has failed to score a touchdown on eight series spanning two preseason games, netting only a pair of field goals against the Panthers. That production was clearly hurt by the loss of Charles, who is arguably the most valuable player on the entire roster.

The defense has continued to give up big plays, particularly in the downfield passing game against a secondary that is still missing Pro Bowl safety Eric Berry to his own injury. Carolina put up two touchdowns apiece in the second and third quarters on Sunday night.

Fundamentals remain problematic — things such as blocking, tackling and route running. And the yellow laundry that littered the field did little to make Reid feel good about discipline — Kansas City was flagged 13 times for 131 yards compared to four times for 32 yards for the Panthers.

— The performance of the offensive line has been mediocre at best. Left tackle Eric Fisher, the first overall pick in 2013 draft, was soundly beaten several times by the Panthers’ pass rush, and the rest of the front five fared little better.

— The defensive backfield is still struggling to adapt to the loss of Pro Bowl cornerback Brandon Flowers and starting safety Kendrick Lewis. Ron Parker, Marcus Cooper and Sean Smith are all trying to earn a cornerback job, and all three were penalized during the game.

— The wide receiver race is still begging for someone to step up, particularly with Dwayne Bowe suspended for the season opener. Bowe had five catches for 62 yards against Carolina, but the rest of the wide receivers combined for just seven catches for 91 yards.

“It felt like we were able to move the ball but just couldn’t finish,” Smith said.

Of course, not everything is doom and gloom with two preseason games remaining.

The pass rush was effective in getting after Carolina quarterback Cam Newton, and it already appears that first-round pick Dee Ford will fit seamlessly with fellow outside linebackers Tamba Hali and Justin Houston. And kicker Ryan Succop, being pushed by Cairo Santos, may have solidified his job by kicking a 54-yard field goal against the Panthers.

Then there’s Travis Kelce, who missed all of his rookie season with a knee injury. The tight end caught a long touchdown pass against Cincinnati in the Chiefs’ preseason opener, and caught a 43-yard scoring strike from rookie Aaron Murray on Sunday night.

“I do like what he is doing. He just has to keep coming with it,” Reid said. “There’s more than just the route running. You have to be able to run block and detail all of your work there. You sure have to give him credit for the effort that he has given.”